Can closing machine



y 1942- w. K. CABOT CAN CLOSING MACHINE Filed June 30, 1939 INVENTOR 8%a M ATTORNEYS Patented May 19, 1942 UNITED STATES PATENT OFFlC E CANCLOSING MACHINE Walter K. Cabot, Montclair, N. 3., assignor to AmericanCan Company, New York, N. 11., a corporation of New Jersey ApplicationJune 30, 1939, Serial No. 282,285

4 Claims.

chamber of the machine is minimized to such an extent that a uniformlysuper-high vacuum may be readily maintained within the machine chamberat all times.

Another object is the provision of such a can closing machine whereinatmospheric air brought into the machine with the entering cans isexhausted from the machine before the can is introduced into the canclosing chamber so that the entrance and discharge of cans into and fromthe chamber in no way affects the super-high vacuum maintained withinthe chamber.

Another object is the provision of a vacuum can closing machine of thischaracter wherein internal valves, separating a plurality of main andauxiliary vacuum chambers which are exhausted to increasing anddecreasing degrees of vacuum, are utilized to protect an innermosthighly vacuumized closing chamber against fluctuations in its vacuumizedcondition.

Numerous other objects and advantages of the invention will be apparentas it is better understood from the following description, which, takenin connection with the accompanying drawing, discloses a preferredembodiment thereof.

Referring to the drawing, the single figure illustrates a plan view of avacuum can closing machine embodying the instant invention, a part ofthe machine being shown in horizontal section.

As a preferred embodiment of the invention the drawing illustrates theprincipal parts of a vacuum can closing machine of the characterdisclosed in United States Patent 1,670,925, is-

sued May 22, 1928, to N. P. Bach, on Vacuum can sealing machine andmethod." For the purpose of this specification the machine is preferablydivided into a can and cover feeding section and a vacuumizing and cansealing section.

In such a machine filled cans A and can covers B are brought together inthe feeding section from separate sources of supply and while the coversare held in suspension over the cans both cans and covers are introducedinto the vacuumizing and closing section of the machine. In thevacuumizing section air brought in with the cans and their covers isnearly all removed prior to the introduction of the cans and covers intoa highly vacuumized closing chamber where the remaining air is exhaustedand the covers sealed onto the cans.

The sealed cans are then passed intoa chamber having a lower vacuumizedatmosphere before being discharged from the machine. The superhighlyvacuumized closing chamber is thus protected against the entrance of airthereinto by the lower vacuumized chambers which are located on eitherside of it. This prevents fluctuations in the vacuum condition of theclosing chamber and thus provides for better vacuumizing and sealing ofthe cans.

In the feeding section of the machine cans A to be vacuumized and sealedare preferably received on a constantly rotating feed-in disc H and areadvanced by an auxiliary feed-in disc l2 in a continuous processionalong a sinuous path of travel toward the can vacuumizing section of themachine. Parallel curved and straight side guides 13 maintain the movingcans in a single line. I

The can covers B are preferably individually fed from a. supply stack l5included in a cover feeding device N5 of the character disclosed inUnited States Patent 2,102,605, issued December 21, 1937, to N. B. Bachon Can and cover feeding mechanism. This feeding device is preferablylocated adjacent the path of travel of the cans moving across theauxiliary feeding disc l2.

The fed covers B are received in spaced pockets ll of a rotating feedturret l8 and are carried by the turret into a position above the pathof travel of the moving cans A. The turret is also provided with canpockets which are below and which register with the cover pockets andhence as a cover is aligned over the foremost moving can in theprocession this can-is picked up or received by the turret pocket andboth can and cover advance simultaneously.

The can A and its superimposed cover B are received from the feed turretl8 in spaced pockets 2| of a rotating timing turret 22 carried on avertical shaft 23 which also carries a disc 24 for supporting the cans.The timing turret properly spaces adjacent cans in the procession andaccelerates them to a desired speed in preparation for their entranceinto the vacuum section of the machine.

The timed and accelerated cans and their covers are delivered into thevacuumizing section of the machine by a rotating star-wheel 25 mountedon a shaft 26. The star-wheel is provided with spaced prongs 21 whichengage behind a can and its cover and sweep them out of a passing pocket2| of the timing turret as the latter rotates. The star-wheel moves thecans and covers across a stationary platform 28, the covers beingsupported and guided by curved guide rails 29.

The vacuumizing section of the machine includes a housing 3| which ismounted on a main frame 32. The housing is partitioned of! to provide aplurality of chambers which are maintained under vacuum of differentdegrees. The central portion of the housing is provided with spaced andparallel partition walls 33 which together with the housing outer wallsenclose a can sealing chamber 34. This chamber is maintained under ahigh degree of vacuum of pref-.

erabiy 29.75 inches.

Air is withdrawn by way of a pipe 35 communicating with the chamber toproduce the desired vacuum. One end of the pipe is threaded into a wallof the housing while its opposite end leads to a suitable source ofvacuum such as a tank or the closing chamber as hereinbefore mentioned.

On the can and cover entrance side (the left as viewed in the drawing)there is provided in the housing 3| a pre-vacuumizing chamber 4| whichis isolated from the closing chamber by a rotary transfer valve 42mounted on a vertical shaft 43 and located in a cylindrical valve seat44 which surrounds the valve.

The valve seat 44 is in substance a partition wall which separates theprevacuumizing chamber from the closing chamber. Can and cover entranceand exit ports 46, 41 are provided in the valve seat and spaced pockets48 are provided in the valve for receiving the cans and covers. Aprevacuumizing condition of between 20 to 26 inches of vacuum ismaintained in this chamber by the use of a pipe 49 which leads to thesource of vacuum.

An opening 5| in a wall of the housing 3| is provided for the entranceof cans and covers into the prevacuumizing chamber. This opening isprotected against the entrance of the outside atmospheric air by arotary entrance valve 52 which is mounted on a vertical shaft 53. Thevalve 52 rotates in a cylindrical valve seat 54 which is secured to theside of the housing 3| adjacent the opening 5|. Entrance and exit ports56, 51, respectively, are provided in the seat for the passage of cansand covers therethrough and spaced pockets 58 are provided in the valvefor the cans and covers.

Thus when a can A and its superimposed cover B are transferred by thestar-wheel 25 from the feed-in section of the machine into thevacuumizing section, the can and cover pass through the entrance port 56of the entrance valve seat 54 and are deposited in a passing pocket 58of the valve. Some of the air taken into the valve pocket along with thecan is immediately dissipated as soon as the pocket is cut-oil? by thevalve seat from communication with the atmosphere.

The partial dissipation of the incoming air is preferably effected by aby-pass pipe 6| the ends of which are secured in the valve seat, one oneach side of the entrance port. The ends of this pipe are located sothat a pocket bringing air and a can and cover into the machine willalign with the end of the by-pass at the same time that an emptyvacuumized pocket which has just dclivered its can and cover into theprevacuumizing chamber will align with the other end of the bypass.I'hus air. in the incoming pocket will flow through the by-pass and intothe vacuumized pocket and thereby equalize the pressures in bothpockets. Hence only a portion of the incoming air is actually carriedinto the prevacuumizing chamber. Z

A can and its cover in a pocket 58 of the entrance valve 52 is carriedaround toward the exit port 51 of the valve seat and is there deliveredby the valve into the prevacuumizing chamber. Delivery of the can andits cover is effected by a finger 53 which is located in the valvepocket. There is one of these fingers in each valve pocket and they areoperated in any suitable manner, such as by a cam or the like. Such aconstruction is common in valves of this character.

The valve finger 63 in delivering the can and its cover into the vacuumchamber 4| through the housing opening 5| sweeps each can and coveracross a guideway 65 disposed in the housing opening and pushes the sameinto a passing pocket 48 of the transfer valve 42. It is during thistransfer of the can that it is prevacuumized.

The transfer valve 42 carries its can and cover toward the can closingchamber 34. During this passage more of the air remaining in the valvepocket in which the can and cover are disposed, is dissipated in thesame manner as described in connection with the entrance valve. This isaccomplished by a by-pass pipe 51 the ends of which are secured in thevalve seat 44 on opposite sides of the seat entrance port 46 in the sameway as in the by-pass feature of the entrance valve seat 54.

When the pocket of the valve 42 comes adjacent the seat exit port 41,fingers 89 similar to those located in the entrance valve pockets, pushthe can and cover out into the can closing or sealing chamber 34. Thecan and its cover are received on a runway II which extends across theclosing chamber. The can and cover are propelled along this runway bycam operated fingers 12 disposed in the chamber. These fingers and theirmode of operation are described in detail in the first mentioned Bachpatent.

Near the center of the runway the can and cover are brought to rest on alifter plate 13 which operates to lift both the can and its cover upinto a closing mechanism such as a seaming head or the like locateddirectly above the lifter plate and within the chamber. Such a closingmechanism is disclosed in the first mentioned Bach patent and it is thismechanism which unites the cover with the can.

After being closed the can is lowered by the lifter plate 13 to itsoriginal level and the feed fingers 12 again operate to discharge thecan by way of the runway H from the closing chamber 34. The closed canis pushed out through the chamber exit opening 38 and is received in apassing pocket 15 of a rotary auxiliary transfer valve 18. The valve iscarried on a vertical shaft l1 and is disposed within a valve seat 13'secured to the adjacent partition wall 33. The valve seat is providedwith an entrance port T9 through which the closed can passes upon beingintroduced into the valve pocket and an exit port 8| through which theclosed can is delivered as the valve rotates.

The auxiliary transfer valve 16 and its seat 18 close oil the dischargeside of the closing chamber 34 from a discharge chamber 43 which islocated in the housing 3|. This chamber is maintained under a vacuum ofapproximately 26 inches by way of a communicating pipe 84 which leads tothe source of supply of vacuum.

The closed can thus introduced into the discharge chamber is subjectedto a slight pressure over that maintained in the closing chamber but yetis a lower pressure than that of the outside atmosphere. It is thisvacuumized discharge chamber which prevents the outside atmospheric airfrom leaking into the closing chamber from the exit side of the machine.

A by-pass pipe 85 having its ends secured in the valve seat 18 adjacentto and on opposite sides of the exit port 8| serves in the same capacityas the by-pass pipes GI, 61 on the other valve seats to prevent airwithin the discharge chamber from being carried into the closingchamber.

The vacuum maintained within the discharge chamber 83 is prevented frombeing dissipated when the closed can is discharged therefrom by adischarge valve 81 having spaced can pockets 88. This valve is mountedon a vertical shaft 99 and is disposed in a cylindrical seat 90 securedto the end wall of the housing 3| adjacent to and surrounding adischarge or can exit opening 9| formed therein. This valve seat isprovided with entrance and exit ports 92,93, respectively. The entranceport is in communication with the chamber opening 9| while the exit portleads to atmosphere.

A closed can in a pocket of the auxiliary transfer valve 16 is deliveredinto the discharge chamber 83 by fingers 95 which are similar to thefillgers 63, 69 in the entrance valve 52 and the transfer valve 42. Thefingers 95 sweep the can across a guideway 96 located in the dischargechamber opening 9| and push it through the valve seat entrance port 92and into a passing pocket 88 of the discharge valve 81.- The valve 81carries the can adjacent the seat exit port 93 where valve fingers 91,similar to the fingers 63, 69, 95, discharge the cans from the valve. Itis then in the atmosphere and may be further moved as desired to anysuitable place of deposit.

A by-pass pipe 98 having its ends secured in the discharge valve seat 90adjacent its exit port 93 acts in the same manner as the other by-passpipes hereinbefore mentioned to partially dissipate atmospheric airentering with the empty pockets of the valve before the pocketscommunicate with the vacuumized discharge chamber 83.

It is thought that the invention and many of its attendant advantageswill be understood from the foregoing description, and it will beapparent that various changes may be made in the form, construction andarrangement of the parts without departing from the spirit and scope ofthe invention or sacrificing all of its material ad vantages, the formhereinbefore described being merely a preferred embodiment thereof.

I claim:

1. In a vacuum can closing machine, the combination of a housing havingcan entrance and can discharge openings therein adjacent oppositeportions thereof, outer valve seats disposed exteriorly of said housingadjacent and surrounding said openings, outer rotary valves havingspaced pockets mounted in said seats for preventing air from enteringsaid housing, partition walls formed with entrance and exit openingslocated inside said housing and setting oiI therebetween a highlyvacuumized can closing chamber adapted to receive cans and covers fromthe pockets of one of said valves and to chamber and an auxiliary sealedcan discharge chamber on the other side, and means for maintaining saidauxiliary chambers under a lesser vacuum than that obtaining in saidclosing chamber for protecting the closing chamber against fluctuationsin its highly vacuumized condition.

2. In a vacuum can closing machine, the combination of a housing,partition walls in said housing setting off therebetween a highlyvacuumized can sealing chamber with a can prevacuumizing chamber on oneside thereof and a sealed can discharge vacuumizing chamber on the otherside for protecting said closing chamber against fluctuations in itshighly vacuumized condition, said partition walls and said housinghaving openings through which cans and covers and sealed cans may bepassed intoand out of said chambers, means for passing said cans andcovers through said sealing chamber in a substantially straight path oftravel during the sealing operation, inner valve seats disposed adjacentthe openings in said partition walls and carrying valves having pocketsfor sealing off said chambers one from the other, and outer valve seatsdisposed adjacent the openings in said housing and carrying valveshaving pockets for sealing ofi said chambers from the outside atmospherethereby protecting said prevacuumizing chamber and said can dischargechamber from the outside atmosphere.

3. In a vacuum can closing machine, the combination of a housing havingcan entrance and can discharge openings therein, entrance and exitvalves having spaced pockets disposed in said housing openings forconveying cans into and out of said housing while excluding atmosphericair therefrom, can feeding\devices adjacent said housing for feedingcans, cover feeding devices for bringing can covers into superimposedposition relative to said fed cans, timing instrumentalities for saidcans and covers, means for introducing said timed cans and covers into apocket of said entrance valve, partition walls having entrance and exitopenings in said housing and setting off a highly vacuumized can closingchamber for the reception of cans for sealing, inner entrance and exitvalves having spaced pockets adjacent said partition wall openings andsetting 011 a vacuumizing chamber on each side of said closing chamber,said vacuumizing chambers being maintained under a lesser vacuum thansaid closing chamber for protecting the latter against fluctuations inits highly vacuumized condition.

4. In a vacuum can closing machine, the combination of a housing havingcan entrance and can discharge openings therein, outer valve seatshaving can entrance and can exit ports adjacent said openings, outerrotary can entrance and exit valves having spaced pockets mounted insaid valve seats, partition walls having can entrance and exit openingsin said housing and setting off therebetween a highly vacuumized canclosing chamber, inner valve seats having can entrance and exit portsadjacent, said partition openings, inner rotary valves having spacedlesser vacuum than that obtaining in said closing chamber for protectingthe latter against fluctuations in its highly 'vacuumized condition,and-'- by-pass pipes associated with said rotary-valve seats andcommunicating with the moving pockets oi said valves while they areisolated by said valve seats for dissipating pocketed air being carriedinto the adjacent vacuum chamber.

WALTER K. CABOT.

